An investigation of both host cell and viral nucleic acid synthesis in cells infected with either Fowlpox virus or Juncopox virus (both of which induce hyperplasia in vivo) will be undertaken by a variety of current, pertinent methods. Special attention will be devoted to studies of viral mRNA synthesis and viral DNA replication. Investigation of the enzymatic content of Avian viruses will be continued. BIBLIOGRAPHIC REFERENCES: Lyles, D. S., C. C. Randall, L. G. Gafford and H. B. White, Jr. 1976. Cellular fatty acids during fowlpox virus infection of three different host systems. Virology, in press. Lyles, D. S., C. C. Randall and H. B. White, Jr. 1975. An alteration in the kinetic properties of a cholesterogenic enzyme in Fowlpox virus infection. Virology 66: 106-116.